Remote access to electronic meters using a TCP/IP protocol suite

ABSTRACT

An electronic meter incorporates a TCP/IP protocol suite and an HTTP server to provide two-way access to the meter data. Alternatively, the TCP/IP protocol suite may be incorporated into a gateway serving multiple meters connected through a power line or wireless two-way network. The gateway may incorporate an HTTP server for accessing data from multiple meters and for transmission of data to individual meters. Other aspects of the disclosed system include the use of a common gateway interface for remote access to meter data and to set meter parameters using HTML forms in HTTP browsers; remote reading and setting of multiple meter parameters using a TCP/IP protocol suite; a TCP/IP protocol suite implemented in designated nodes in a CEBus LAN with remote access through TCP/IP to routers and brouters and to individual meters on the LAN; and an SLIP-PPP enabled gateway for remote TCP/IP access through a serial interface to a single or multiple meter parameters.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of U.S. patent applicationSer. No. 09/975,582, filed on Oct. 10, 2001, which is a continuation ofU.S. patent application Ser. No. 09/022,718, filed on Feb. 12, 1998,which claims priority to U.S. provisional patent application No.60/039,716, filed on Feb. 12, 1997.

FIELD OF THE INVENTION

[0002] The present invention relates generally to electronic meters andautomatic meter reading, and more particularly to TCP/IP-enabledelectronic meters for remote two-way access over local area networks andwide area networks.

BACKGROUND OF THE INVENTION

[0003] The present invention relates to automatic meter reading (AMR)systems for use in automatically reading electrical energy and otherutility meters (e.g., water and gas meters). The invention is moreparticularly intended for, although not limited to, use in an electronicmeter. Further background information on electronic meters can be foundin U.S. Pat. No. 5,548,527, Aug. 20, 1996, titled “ProgrammableElectrical Energy Meter Utilizing a Non-Volatile Memory” (assigned toABB Power T&D Company Inc.) Further background on automatic meterreading systems can be found in U.S. Pat. No. 5,553,094, Sep. 3, 1996,titled “Radio Communication Network for Remote Data GeneratingStations.”

SUMMARY OF THE INVENTION

[0004] The present invention, as discussed in greater detail below,involves the use of a TCP/IP protocol suite and a hypertext transferprotocol (HTTP) server. The terms “HTTP” and “TCP/IP” are well known inthe networking and telecommunications arts. For example, TCP/IP refersto a well known set of protocols for linking dissimilar devices acrossnetworks. The invention also involves the use of a “gateway”. A gatewayis a node in a network that connects two otherwise incompatiblenetworks. Gateways may perform code and protocol conversion processes. A“protocol” is a set of rules or procedures relating to the format andtiming of data transmissions between two devices. Protocols typicallybreak a file into equal-size blocks or packets. These are sent and thereceiving device uses a mathematical procedure to determine whether theblock or packet was received accurately.

[0005] An electronic metering system in accordance with the presentinvention comprises a wide area network (WAN) operating in accordancewith a TCP/IP protocol; a local area network (LAN) comprising aplurality of meters each of which includes meter electronics formeasuring a prescribed quantity supplied by a utility and memory forstoring measured data and meter control parameters; a gatewayoperatively coupled to the LAN and the WAN; and an HTTP serveroperatively coupled to the LAN and the gateway, whereby the WAN isprovided remote access to the measured data and control parameters ofthe meters.

[0006] Presently preferred embodiments of the invention further includea CGI (common gateway interface) application coupled to the HTTP serverfor use in accessing the measured data. Alternatively, the inventivesystem may include a virtual machine coupled to the HTTP server for usein accessing the data.

[0007] The prescribed quantity is preferably electricity, water or gas.

[0008] The HTTP server and CGI application may be embedded in each ofthe meters or, alternatively, embedded in the gateway.

[0009] Other features of the present invention are disclosed below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 schematically depicts an AMR network comprising a wide areanetwork 10, gateway 20, local area network 30 and meters 40, inaccordance with the present invention.

[0011]FIG. 2 schematically depicts an embodiment of the presentinvention in which an HTTP server and a common gateway interface arelocated in the meter(s) 40.

[0012]FIG. 3 schematically depicts an embodiment of the presentinvention in which an HTTP server and a common gateway interface arelocated in the gateway 20.

[0013]FIG. 4 illustrates how the common gateway interface could bereplaced by a Java virtual machine and a Java applet.

[0014]FIG. 5 portrays an embodiment of the invention in which one ormore computers are given access to the meters by way of a PPP server orinterface.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0015] The present invention, in one embodiment, employs an electronicmeter incorporating a TCP/IP protocol suite and an HTTP server fortwo-way access to the meter data. In another embodiment of theinvention, the TCP/IP protocol suite is incorporated into a gatewayserving multiple meters connected through a power line or wirelesstwo-way network. The gateway employed in a second embodiment of thepresent invention incorporates an HTTP server for accessing data frommultiple meters and for transmission of data to individual meters.

[0016] The basic architecture of the present invention is shown inFIG. 1. As mentioned, embedding an HTTP server and a TCP/IP protocolstack within a meter 40 or a gateway 20 to multiple meters through alocal area network (LAN) 30 enables remote access to meter parameters ona continuous basis. As shown, a set of N meters 40 communicate through anon-TCP/IP type of LAN 30. The LAN 30 may be, e.g., a CEBus networkemploying power line or radio frequency communications (the ConsumerElectronics Bus (CEBus) protocol has been adopted as an ElectronicsIndustry Association standard (EIA IS-60), and defines a LAN that usesmultiple media, including power line, radio, twisted pair, coaxialcable, and infrared signaling). Also connected to the LAN 30 is agateway 20 that is also connected to a TCP/IP wide-area network (WAN)10. Other applications (not shown) are also connected to the TCP/IP WAN10 and may need to access the individual meters or groups of meters.These applications access individual meters by sending commandscontained in packets with attached TCP/IP destination addresses that areunique to each meter.

[0017] In the first implementation of the invention (FIG. 2), thegateway 20 receives packets from other applications on the WAN 10. Thegateway 20 includes a TCP/IP interface 22 and a LAN interface 28. TheLAN interface 28 includes software for transforming the data packetsinto the format required for transmission on the LAN 30. The gateway 20then transmits these reformatted packets over the LAN 30 to the meters40. The steps involved in this transformation are:

[0018] 1. The gateway examines the TCP/IP address of the packet anddetermines if it is the address of a meter or meters within the setattached to the gateway through its LAN. If not, the packet is ignored.

[0019] 2. If the packet is intended for one of the meters on thegateway's LAN, the gateway examines the meter TCP/IP address attached tothe packet and determines if it is an individual meter address or abroadcast address.

[0020] 3. If the packet is addressed to an individual meter, then thegateway encapsulates the packet into a larger packet that is addressedto the meter using its unique LAN address (which is different from itsTCP/IP address).

[0021] 4. If the packet is meant for broadcast to all the meters, thenthe gateway encapsulates the packet into a larger packet addressed tothe special broadcast address of the LAN (which is different from theTCP/IP broadcast address).

[0022] 5. If the packet is larger than the maximum allowable packet sizefor the LAN, then the gateway segments the packet into smaller pieces.Each piece is labeled with the same LAN address as the original, largerpacket.

[0023] 6. Each piece of the segmented packet is transmitted onto the LANfor reception by one or more of the meters. The gateway is responsiblefor receiving acknowledgments of packet receptions from the meters, andfor retransmitting packets if they are not received.

[0024] Each individual meter listens on the LAN for packets. A meterreconstitutes the original TCP/IP WAN packet from one or more LANpackets, and then executes the commands contained in the packet andsends the results back to the gateway. The steps involved in thisprocess are:

[0025] 1. The meter examines the LAN address of the packet to see if itis intended for this meter or is a broadcast address. If the address isneither of these, the meter ignores the packet.

[0026] 2. If the packet is specifically addressed for the meter, anacknowledgment of reception is sent back to the gateway. If an error isfound in the packet, a negative acknowledgment is sent back to thegateway. For broadcast transmissions, no acknowledgment is sent.

[0027] 3. The received packet is appended to any previously receivedpieces of the larger segmented packet. When all of the pieces of thesegmented packet are received, the entire original TCP/IP packet isextracted and sent to the TCP/IP interface software, in the meter.

[0028] 4. The TCP/IP interface software examines the packet to see whatservice is being requested. In this case, assume the packet is intendedfor servicing by the HTTP server. (It is possible that there could beother servers running on the meter to which TCP/IP messages could besent.)

[0029] 5. The HTTP server examines the data packet to see what operationis being requested. In this case, assume that the packet contains arequest that an application program be run on the meter to extract itscurrent reading and send it back to the originator of the request. TheHTTP server will initiate this application through the CGI.

[0030] 6. The CGI application will query the meter application softwareto find the current reading. The meter application directly accesses themeter electronics to get the required information. The reading is passedback to the CGI application, which writes the reading into a messageusing HTML. The HTML message is sent back lo the HTTP server.

[0031] 7. The HTTP server encodes the HTML message as a TCP/IP packetand sends it on to the meter's TCP/IP interface.

[0032] 8. The meter's TCP/IP interface sends the packet to the gatewayusing the same set of steps that the gateway used to send the originalrequest to the meter.

[0033] 9. Once the gateway receives the TCP/IP packet from the meter, itretransmits the packet onto the WAN where the originating applicationfor the command can receive it.

[0034] In the second embodiment of the invention (FIG. 3), the gatewayassumes most of the tasks assigned to the meters in the first embodiment(FIG. 2). The HTTP server 24 and CGI application 26 are moved to thegateway 20, and the meters retain only their interface 42 to thenon-TCP/IP LAN. The processing of packets received from the WAN 10proceeds as follows:

[0035] 1. The gateway examines the TCP/IP address of the packet anddetermines if it is the address of a meter or meters within the setattached to the gateway through its LAN. If not, the packet is ignored.

[0036] 2. The TCP/IP interface software examines the packet to see whatservice is being requested. In this case, assume the packet is intendedfor servicing by the HTTP server now contained in the gateway. (It ispossible that there could be other server applications running on themeter to which TCP/IP messages could be sent.)

[0037] 3. The HTTP server examines the data packet to see what operationis being requested. In this case, assume that the packet contains arequest that an application program be run to get the current reading ofan individual meter and send it back to the originator of the request.The HTTP server will initiate this application through the CGI (26).

[0038] 4. The CGI application 26 now runs within the gateway. It mustdetermine the LAN address of the specified meter and send a commandpacket to it over the LAN.

[0039] 5. The command is received by the meter and causes the meterapplication to query the electronics to find the current reading.

[0040] 6. The meter reading is encapsulated into a LAN packet and sentback to the gateway.

[0041] 7. The CGI application receives the LAN packet from the meter andextracts the meter reading. The reading is written into an HTML messageand is sent back to the HTTP server.

[0042] 8. The HTTP server encodes the HTML message as a TCP/IP packetand sends it on to the gateway's TCP/IP interface 22.

[0043] 9. The gateway's TCP/IP interface 22 sends the packet onto theWAN 10 where the originating application for the command can receive it.

[0044] Both implementations of the present invention have been describedas using CGI applications 46, 26 to handle the details of accessing thecurrent reading for a meter. As shown in FIG. 4, the CGI applicationcould be replaced by a Java virtual machine (VM) 26′ running a Javaapplication 26″ that performs the same operations as the CGIapplication.

[0045] In addition, both implementations have been described using anexample where the current reading of an individual meter is requested byan application connected to the WAN. An application on the WAN can alsowrite data to a meter or meters using similar procedures. The data couldmodify parameters affecting the operations of the meter or meters. Anexample would be rate updates.

[0046] Either implementation, with their use of TCP/IP and HTTP servers,supports the reading of meters or setting their parameters usingbrowsers such as a Netscape™ or Explorer™. Utilities and homeownerscould perform remote on-demand meter reading via their browsers. Anindividual meter or group of meters could be accessed as if the meter(s)were a web site and their current readings or other data could bedisplayed on the browser. The meters could send forms to the browserthat the user could fill in to change parameters in the meters. Bothreading and updating the meters would be protected by encryption andpasswords.

[0047] As shown in FIG. 5, a browser could gain access to the metersthrough a phone line to a Point-to-Point Protocol (PPP) server 60attached to the WAN 10 or attached directly to a gateway 20. The PPPserver interfaces with modems (not shown) to provide a TCP/IP link to abrowser on the other end of the line. The PPP server sends the packetsfrom the phone line onto the WAN where they are received by theappropriate gateway. In the case of a phone line connection directly toa gateway, the PPP software includes an interface 21 for directlyconnecting to the TCP/IP WAN interface 22 so that the packets receivedover the phone line are handled in the same way as packets received overthe WAN 10.

[0048] The browser may be replaced by an intelligent application programthat accesses the HTTP server for automated meter reading and parametersetting on a scheduled and repetitive basis. The application uses themeter readings to create or update records in a database. Thisapplication could be a Java application which can interact with the HTTPservers and databases that support the HTTP protocols.

[0049] In sum, the present invention includes the following novelaspects: (1) Embedded HTTP server in a meter for on-demand access tometer data and for remotely setting meter parameters; (2) Embedded HTTPserver in a gateway to multiple meters to read and set parameters inindividual meters on a LAN; (3) Using CGI for remote access to meterdata and to set meter parameters using HTML forms in HTTP browsers; (4)Remote reading and setting of multiple meter parameters using TCP/IPprotocol suite; (5) TCP/IP protocol suite implemented in designatednodes in a CEBus LAN including CEBus routers and brouters with remoteaccess through TCP/IP to the router/brouter and, therefore, individualmeters on a LAN; (6) SLIP-PPP enabled gateway for remote TCP/IP accessthrough a serial interface (phone line, or ISDN, for example) to asingle or multiple meter parameters (setting and reading).

[0050] The foregoing detailed description of preferred embodiments ofthe invention is not meant to limit the scope of protection of thefollowing claims. Those skilled in the art of electronic metering willrecognize that many modifications may be made to the presently preferredand specifically described embodiments without departing from the truespirit of the invention.

What is claimed:
 1. An electronic metering system, comprising: (A) awide area network (WAN) operating in accordance with a TCP/IP protocol;(B) a local area network (LAN) comprising a plurality of meters each ofwhich includes meter electronics for measuring a prescribed commoditysupplied by a utility and memory for storing measured data and metercontrol parameters; (C) a gateway operatively coupled to said LAN andsaid WAN; and (D) a server operatively coupled to said LAN and saidgateway, whereby said WAN is provided remote access to said measureddata and control parameters of said meters.
 2. A system as recited inclaim 1, further comprising a common gateway interface (CGI) applicationcoupled to said server for use in accessing said measured data.
 3. Asystem as recited in claim 2, wherein said server and said CGIapplication are embedded in each of said meters.
 4. A system as recitedin claim 3, wherein each of said meters further comprises a TCP/IPinterface.
 5. A system as recited in claim 2, wherein said server andsaid CGI application are embedded in said gateway.
 6. A system asrecited in claim 1, further comprising a virtual machine coupled to saidserver for use in accessing said data.
 7. A system as recited in claim1, wherein each of said meters further comprises a LAN interface.
 8. Asystem as recited in claim 1, wherein said gateway comprises a LANinterface.
 9. A system as recited in claim 1, wherein said gatewaycomprises a TCP/IP interface.
 10. A system as recited in claim 1,further comprising a common gateway interface (CGI) application coupledto said server for use in accessing said measured data; wherein saidserver and CGI application are embedded in each of said meters; whereinsaid gateway and each of said meters comprises a LAN interface and aTCP/IP interface; and wherein said prescribed commodity is a member ofthe group consisting of electricity, water and gas.
 11. A system asrecited in claim 1, further comprising a common gateway interface (CGI)application coupled to said server for use in accessing said measureddata; wherein said server and CGI application are embedded in saidgateway; wherein each of said meters and said gateway comprises a LANinterface; wherein said gateway further comprises a TCP/IP interface;and wherein said prescribed commodity is a member of the groupconsisting of electricity, water and gas.
 12. An electronic meter,comprising: meter electronics for measuring a prescribed commoditysupplied by a utility; a memory for storing measured data and metercontrol parameters; and a server operatively coupled to said meterelectronics and memory; said electronic meter being configured for usein a system including a wide area network (WAN) operating in accordancewith a TCP/IP protocol, a local area network (LAN), and a gatewayoperatively coupled to said LAN and said WAN, whereby said WAN isprovided with remote access to said measured data and control parametersof said electronic meter.
 13. An electronic meter as recited in claim12, further comprising a LAN interface and a TCP/IP interface operatingin the meter.
 14. An electronic meter as recited in claim 12, furthercomprising a common gateway interface (CGI) application and a meterapplication operating in the meter.
 15. A gateway for use in a systemcomprising an electronic meter connected to a local area network (LAN),the gateway, and a wide area network (WAN) operating in accordance witha TCP/IP protocol, wherein the electronic meter is operatively coupledto the WAN through the gateway, the gateway comprising: a serverembedded in the gateway and operatively coupled to said electronicmeter, whereby said WAN is provided with remote access, via the gatewayto measured data and control parameters of the electronic meter.
 16. Agateway is recited in claim 15, further comprising a LAN interface and aTCP/IP interface embedded in the gateway.
 17. A gateway as recited inclaim 15, further comprising a common gateway interface (CGI)application operating in the gateway.
 18. A method for operating anelectronic metering system, comprising: (A) providing a wide areanetwork (WAN) operating in accordance with a TCP/IP protocol; (B)coupling the WAN to a local area network (LAN) comprising a plurality ofmeters each of which includes meter electronics for measuring aprescribed commodity supplied by a utility and memory for storingmeasured data and meter control parameters; (C) providing a serveroperatively coupled to said LAN; and (D) providing said WAN with remoteaccess to said measured data and control parameters of said meters.